Abstract

The objective of the present work was to reach a better understanding of the molecular mechanisms leading pre-implantation development through the analysis of the quality of the ovine oocyte and embryo with molecular biology techniques. More specifically, we have questioned the value of the gene expression analysis as a means of evaluation of the developmental capacity.
We have evaluated the gene expression profiles in a model of differential developmental competence consisting of prepubertal and adult oocytes and embryos, together with the effects of different in vitro culture conditions. Furthermore, we analysed the capacity of development in absence of fertilization in correlation with the gene expression status of parthenogenetic embryos .
Overall, results show that oocytes and embryos exposed to different conditions or with different origins display unlike patterns of expression, in association with diverse developmental competence. The genes showing an altered expression differ on the basis of the diverse stimulus or origin, showing the capacity of oocytes and embryos to respond to sub-optimal conditions and giving an opportunity to identify potential markers of developmental competence.
Increased understanding of the gene expression status during pre-implantation development may provide valuable insights into the molecular basis underlying the very early stages of life and a fundamental opportunity for optimizing in vitro and in vivo embryo production systems.